bcachefs: mark bch_inode_info and bkey_cached as reclaimable

Mark these caches as reclaimable, so that available memory is correctly
reported when there is a lot of cached inodes.

Note that more work is needed - you should add __GFP_RECLAIMABLE to some
of the kmalloc calls, so that they are allocated from the "kmalloc-rcl-*"
caches.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_key_cache.c

@@ -1066,7 +1066,7 @@ void bch2_btree_key_cache_exit(void)
 
 int __init bch2_btree_key_cache_init(void)
 {
-	bch2_key_cache = KMEM_CACHE(bkey_cached, 0);
+	bch2_key_cache = KMEM_CACHE(bkey_cached, SLAB_RECLAIM_ACCOUNT);
 	if (!bch2_key_cache)
 		return -ENOMEM;
 

fs/bcachefs/fs.c

@@ -1926,7 +1926,7 @@ int __init bch2_vfs_init(void)
 {
 	int ret = -ENOMEM;
 
-	bch2_inode_cache = KMEM_CACHE(bch_inode_info, 0);
+	bch2_inode_cache = KMEM_CACHE(bch_inode_info, SLAB_RECLAIM_ACCOUNT);
 	if (!bch2_inode_cache)
 		goto err;